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Chemistery Question(concerning rate equation)

Salman

this was given for practice but i am not sure how to calculate order of reation

A+B+C-----> ABC

[A]/moldm^-3 .1 .2 .2 .1
/moldm^-3 .1 .1 .2 .1
[C]/moldm^-3 .1 .1 .1 .2
Rate 3 6 24 6

I have to calculate the value of K

Reply 1

dinesh

well
A B C Rate
1 1 1 3
2 1 1 6
2 2 1 24
1 1 2 6

So as can be seen when the conc of A is doubled, the rate doubles,therefore it is 1st order
or using the eq calculation:
Rate1 = [Conc1 / Conc2 ]^n , where N=order of reaction
===
Rate 2

For B, as A is constant and B is constant, B doubles, and the rate goes up by
24/6 =(2/1)^n
therefore, 4=2^n, therefore n=2

Look at athe last reaction, as C is doubled, the rate also doubles, therefore it is 1st order wrt to C

USe any of the values in the table I have drawn up and put
Rate=K X [a]X ^2 X [c]
and solve for K